1. Field of the Invention
The present invention relates to a manufacturing method for double-side capacitor of stack DRAM, and in particular to a manufacturing method for double-side capacitor of stack DRAM with simplified steps which is provided for manufactures stack DRAM with high capacity.
2. Description of Related Art
The random access memory (RAM) is a form of computer data storage, which includes transistors, capacitors and peripheral controlling circuit. For increasing the computer performance, it is important to increase the surface of the capacitors so as to improve the electric charge stored on the capacitors.
Double-side capacitors have been studied because of the higher capacity of the electric charges. Moreover, the height of the memory cell can be reduced so that the size of the device can be reduced.
However, the traditional manufacturing method for the double-side capacitor has complicated steps; for example, the precision of alignment of the lithograph is higher than the single-side capacitor. Therefore, the manufacturing yield is too low. On the other hand, the structure of the traditional double-side capacitor is weak so that the electrodes of the capacitor are easily collapsed. Thus, the function of RAM is failed.
In view of the above, the present Inventor proposes a thin key structure capable of reducing the total thickness and weight of the key structure, whereby the key structure becomes more compact and user-friendly to generate a steady operation.